The present invention relates to a chain conveyor provided with two chains connected together by scrapers, which circulate inside a casing consisting of bottom and side walls and are guided around rollers.
Chain conveyors of this class can be used as wet ash removers and disposed below the combustion chamber or a gas flue of a steam boiler. For such an application, the conveyors must be capable of storing a specific quantity of ash when the conveyor for various reasons is out of action, or very large quantities of ash suddenly arrive from the combustion chamber. It must then be possible to extract these quantities without difficulties when the conveyor is started up again.
In particular, in the case of so-called soot blowing, the conveyors may be filled up to the upper edge of the casing. When the conveyor is switched on again, an ash build up can occur in the region of the change-direction rollers disposed at the transition from the horizontal to the inclined portion of the conveyor. Due to the low degree of filling in the inclined portion, the ash builds up at the transition. The conveyor thereby comes to a stop after a short time. It has been found that the chains force the ash underneath the change-direction rollers. Due to the wedging action of the roller radii, the ash is compacted, so that a blockage occurs here.